Cable equalizer



J. DUNLOP CABLE EQUALIZER INVENToR James Dwnlnyl ATTORNEY .April v28,* 1931.

Filed Dec. '7. 1928 Patented Apr. 28, 1931 UNITED stares intatta PATEN OFFICE JAMES DUNLOP, OF CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO NESTv INGHOUSE ELECTRIC ELEVATOR COMPANY, A CORPORATION OF ILLINOIS CABLE EQUALIZER Application filed December My invention relates to hoisting drums employed for operating a plurality of cables and it has special relation to means for equalizing the pull exerted by the hoisting drums `5 upon the cables.

In modern elevator installations, it is usual to employ a car of such Weight and designed to carry such loads that itis necessary to support the car structure upon a plurality 1,0 of cables that pass over, and are driven by,

a hoisting drum in the upper part of the elevator shaft. Ordinarily, the cables are disposed in suitable grooves of V-shape in the hoisting drum in order to insure sufficient 1,5 traction to cause the drum to exert the desired pull upon the cables in operating the elevator.

It is Well known, however, that the pull exerted upon the individual cables by the 20 hoisting drum varies considerably from time A to time by reason of the slipping of the cables on the drum, the stretching of the cables or other causes. lVhen the pull upon the individual cables diers,\ the greater part of the 25 load of the elevator may be carried by only a small number of the cables and thereby subject them to excessive strain and Wear.

Therefore, it is an object of my invention to provide for equalizing the pull exerted by a hoisting drum upon a plurality of loadbearing cables in such manner that all cables will carry equal shares of the load.

A further ob]- eet ot' my invention is to provide a means for equalizing the pull exerted r by a hoisting drum on a plurality of cables that will permit the employment of hardcned-steel cables and hardened-steel supporting members therefor and thereby insure a longer life for the cables as Well as for the drum.

It is also an object ofmy invent-ion to provide a hoisting apparatus that shall be simple and etlicient in operation and adapted for ready and economical manufacture, installation and repair.

ther objects of the invention will, in part, be obvious and Will, in part, appear hereinafter. Y

For an illustration of one of the various forms my invention may take, reference may 7, 1928. Serial No. 324,554.

be had to the accompanying drawing, in which:

Figure 1 is a view, in end elevation, partly broken away, of an elevator-hoisting apparatus constructed in accordance with my in- 55 vention; and

Fig. 2 is a View, in section, taken on the lines II-II of Fig. 1.4

In the drawing, I have indicated a car C (only the main supporting beam of Which is shown) as suitably suspended by a plurality of cables 1, 2, 3, 4, 5 and v6 which pass over a hoisting drum D and a positioning pulley lP to a suitable counter-Weight Cl/V (only the supporting beam of which is shown). The C5 hoisting drum is illustrated as'mounted upon, and keyed to, an operating shaft 7 Which'may be driven by any suitable source of power, such as an electric motor (not shown).

. In order that the pull exerted by the hoisting drum upon thecables may be equally distributed among them When the elevator car C is being operated, the cables are supported upon the drum by a plurality or" tractionequalizing rings 8, 9, 10, 11 12, 13, and 14 that are provided With cooperating angular faces which form grooves of V -shape in which the cables ride.

The equalizing rings 8, 9, 10,11, 1Q, 13 and 1d are loosely mounted on the outer periphery o or face of the drum in a recess or groove 15 that is formed by a pair of cooperating flange rings 16 and 17 vin such manner as will permit lateral movement of the rings in the grooves. lIhe'iiange ring 16 is shown as constituting an integral part of the drum D, While `the cooperating ange ring 17 for retaining the equalizing rings in position and for limiting their lateral movement is shovvn X as a separate ring that secured to the drum i" by means of a plurality of stud bolts 18. This construct-ion permits the ready removal oi" the rings Jfor repairs or replacements.

In order to prevent the equalizing rings from moving circumferentially relative to "1 the drum D, they are bolted to the flange rings 16 and 17 by a plurality ot cross bolts 19. The transverse holes 20 inthe equalizing rings through Which the cross bolts 19 eX- tend are made suiiciently large to permit the GQ rings to move freely laterally, While preventing them from moving substantially circumferentially relative to the drum.

lVhile the equalizing rings may be constructed of any suitable material, I prefer to make them of hardened ,steel in order to permit the use of hardened-steel cables therewith, thereby insuring a construction having a long life. y

For the purpose of insuring good tractive engagement between the cables and the equalizing rings and, at the same time,` assist in adjusting the load on the cables under various conditions, each cable is attached to the car C and to the counter-weight CV by a suitable resilient connecting means, such as compression springs 21 and 22.

Inasmuch as the equalizing rings 8, 9, 10, 11, 12, 13 and 14 are loosely mounted in the groove 15 on the drum D and may move freely in a lateral direction therein, they will adjust themselves laterally in accordance Wit-h the pressures of the cables 1, 2, 3, e, 5 and 6 in the grooves formed by the angular cooperating faces of the equalizing rings.

For instance, if the cables 2, 3 and 6 slip on the drum or stretch slightly While the drum is rotating, the pull exerted by the drum upon them Will decrease, While the pull and, therefore, the load on the other cables 1, l and 5 Will increase. As the load on the cables 1, fland 5 increases, they Will pull themselves deeper into their grooves, thereby spreading apart the equalizing rings 8 and 9 and 11, 12 and 18. rThe spreading apart of these rings deepens the grooves for the cables 1, 4 and 5, thus permitting them to operate on a. smaller drum diameter and lessening the pull exerted upon them by the drum. At the same time, the spreading apart of the rings 8 and 9 and 11, 12 and 13 causes the rings 9, 10 and 1l, and 13 and 14, to move closer together, thereby causing the cables 2, 3 and 6 to ride in grooves of sligthly larger drum diameter and thus increasing the pull exerted upon them by the drum. Therefore, as the drum continues to rotate, the equalizing rings Will adjust themselves in such manner that the cables 1, 4 and 5 will be relieved of their over-load and the cables 2, 3 and 6 will take an equal share ofthe burden, thus equalizing the pull exerted by the drum upon the individual cables.

Where no means is employed for equalizing the pull upon the cables, a greater part of the load may be carried by only one or tivo of the cables. Hence, traction between the cables and the hoisting drum Will be limited to only those of the cables supporting the greater part of the load While the drum Will exert substantially no tractive pull on the reniainingcables. Therefore, in such installations'., it is usually necessary to employ an idler slieave to obtain a double iviap f tlie cables around the hoisting drum for the purpose of obtaining suflicient traction from the few taut cables to support and move the car. Inasmuch as my invention provides for equalizing the pull upon the cables and thereby insures good traction upon each of the cables, its use, in many instances, will obviate the necessity of employing a construction embodying an idler sheave. l Y

lVhile the illustrated example constitutes a particular embodiment of my invention, I do not limit myself strictly to the details shown, since, manifestly, the same maybe varied considerably Without departing from the spirit of the invention, as defined in the appended claims.

I claim as my invention:

1. The combination With av hoisting drum for a plurality of load-bearing cables, of a ,j

plurality of rings mounted on the drum and having cooperating faces disposed to constitute bearing grooves for the cables, said rings being'movable laterally to permitrthe pressure of the cables on their faces to adjust them in such position as to equally distribute the pull ofthe drum on the cables.

2. The combination with a hoisting drum for a plurality of load-bearing cables, of a plurality o f rings mounted on the drum and having cooperating angular faces disposed to constitute bearing grooves for the cables, said rings being movable laterally to permit the pressure of the cables on their facesl to adjust them in such position as to equallydistribute the pull of the drum on the cables.

3. The combination With a hoisting drum for a plurality of load-bearing cables, of a plurality of rings mounted on the drum and having cooperating angular fa es disposed to constitute bearing grooves for the cables, said rings being movable laterally to permit the pressure of the cables on their faces to adjust them in such position as to equally distribute the pull of the drum on the cables, and means for limiting the lateral movement of the'rings.

j 4. The combination With a hoisting drum for a plurality of load-bearing cables, of a plurality of rings mounted on the drum and having cooperating angular faces disposed to constitute bearing grooves for the cables, said rings being movable laterally to permit the pressure of the cables on their faces to adjust them in such position Vas to equally distribute the pull of the drum on the cables, and means for limiting the circumferential movement While permitting the lateral movement of the rings relative to the drum.

5. The combination `with a hoisting drum for a plurality of load-bearing. cables, of a plurality of rings mounted on the drum and having cooperating angular faces disposed to constitute bearing grooves for the cables, said yriiigs beiiig movable laterally to permit the pressure f the cables on their face's'to adjust them in such position as to equally distribute the pull of the drum on the cables, and a cooperating paii` of flange rings secured to the drum for retaining the rings on the drum and for limiting their lateral movement.

G. The combination with a hoisting drum for a plurality of load-bearing cables, of a plurality of rings mounted on the drum and having cooperating angular faces disposed to constitute bearing grooves for the cables, said rings being movable laterally to permit the pressure of the cables on their faces to adjust them to such positions as to equally distribute the pull of the drum on the cables, and means secured to the Harige rings for limiting the circumferential movement While permitting the lateral movement of the rings relative to the drum.

7. ln hoisting apparatus having a plurality of load-bearing Cables, a hoisting drum having a face provided with a recess, a plurality of rings mounted in said recess and having cooperating angular faces disposed to constitute bearing grooves for the cables, said rings being movable laterally in said recess to permit the pressure of the cables on their faces to adjust them to such positions as to equally distribute the pull of the drum on the cables, and means for limiting the circumferential movement While permitting the lateral movement of the rings relative to the drum.

S. In a hoisting apparatus for an elevator car having a counterweight, a plurality of hoisting cables, resilient means for attaching the cables to the car, resilient means for connecting the cables to the counter-Weight, a hoisting drum for operating the cables, a plurality of equalizing rings mounted on the drum and having angular faces disposed to constitute bearing grooves for the cables, said rings being movable laterally to permit pressure of the cables on their faces to adjust them to such positions as to equally distribute the pull of the drum on the cables, means for limiting the lateral movement of the rings, and means for limiting the circumferential movement While permitting the lateral movement of the rings relative to the drum.

In testimony whereof, I have hereunto subscribed my name this 28th day of November, 1928.

JAMES DUNLOP. 

